A cellular telecommunication network is typically formed by many geographic areas called cells. In a Long Term Evolution (LTE) network, each cell has an associated eNode B, which is the element of the LTE network that communicates directly with mobile handsets (referred to as user equipment or UEs). An LTE eNode B performs traditional functions of a base station and a radio network controller (RNC).
The eNode Bs are each connected to a core telecommunication network through a wired or wireless backhaul and communicate with a mobility management entity (MME) over that backhaul using what is referred to as an S1 logical interface. To communicate with each other, e.g., for telecommunication device handovers or radio resource coordination, eNode Bs use what are referred to as X2 logical interfaces between base stations.
When a UE is idle, the MME may not have current information regarding the exact cell within which the UE is currently located. In order to initiate a call to the UE, the MME sends a paging request to multiple eNode Bs. Upon receiving a paging request, an eNode B pages the UE. If the UE is in the cell associated with the eNode B, the UE receives and responds to the page. The eNode B that receives a response to the page then sends the response back to the MME.